Disposable lids for drinking cups are, of course, very well known. Indeed, disposable lids having drink-through openings are very well known. The advantage of a drink-through opening is that the lid does not need to be removed from the cup in order to drink the beverage which is contained in the cup. This may be particularly advantageous when the beverage is a hot beverage, such as coffee or tea.
For the most part, however, disposable cup lids having a drink-through opening have required that the apron of the cup, which defines its periphery, be broken in order for a tear-back flap to be torn back and folded backwardly so as to reveal the drink-through opening. As soon as the periphery defining apron of the lid is broken, its engagement to the rim of the drinking cup is much less secure. However, the present invention overcomes that difficulty by providing a cup lid having a so-called "plug fit". Moreover, because the periphery defining apron of the cup lid of the present invention remains unbroken and in place on the drinking cup rim at all times, a plug fit may be provided which may extend less than 360.degree. around the periphery.
What is meant by a plug fit is that a recess is formed on the underside of the disposable cup lid, at or very near the outer periphery thereof, and the recess accommodates the lip of the drinking up at both its inside and outside extremities. Thus, the rim of the cup extends upwardly into the recess, which is downwardly directed, and the rim of the cup is much more securely held in place.
Notwithstanding the prior art which is discussed hereafter, the Inventor herein has unexpectedly discovered that disposable cup lids may be provided for placement onto a drinking cup, having a plug fit, and having an unbroken periphery defining apron, where the plane of the substantially circular and substantially planar top surface of the disposable cup lid is at or below the top wall of the downwardly directed recess which provides for the plug fit. Hitherto, most such cup lids that have provided a drink-through opening together with an unbroken periphery defining apron have been dome lids.